1. Field of the Invention
The present invention relates to a tool for measuring, cutting and scoring stock planar material, such as drywall.
2. Description of the Prior Art
The prior art has long attempted to provide a practical tool to cut or score a measured width of drywall or the like, typically employing apparatus intended to be secured to pre-existing tools such as T-squares and tape measures. The following U.S. Pat. Nos. are exemplary of prior art tools: 2,952,025, issued to F. H. Johnson on Sep. 13, 1960; 3,286,351, issued to R. McAlister on Nov. 22, 1966; 4,903,409, issued to S. N. Kaplan et al. on Feb. 27, 1990; 4,949,462, issued to M. P. Spencer on Aug. 21, 1990; and 5,093,375, issued to L. Helm, Sr. on Jan. 28, 1992.
In the prior art, a tee is defined including a guide having a planar surface by which the tool is trued to the sheet of material being cut, and, normal to the planar surface, a member defining a longitudinal axis along which a knife is moved to provide adjustment. The longitudinal member will hereinafter be referred to as the stem. The stem typically bears graduated indicia enabling measurement and appropriate adjustment of the cutting member. In all examples of the prior art known to the applicant, position of the cutting element is adjusted by moving the knife along the stem, the guide being integrally fixed to the stem.
Although this arrangement enables measuring and cutting tools to be readily formed by the simple expedient of mounting a knife slidably to a T-square or similar apparatus, limitations result to the practical use of a tool so formed.
These limitations, and the improvement overcoming these limitations, will be further described hereinafter. None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.